


Karma is a bitch

by Ked_from_safe-skeletons (Sinnychild)



Category: Undertale (Video Game)
Genre: Karmic Retribution, M/M, Safeword Use, Soul Sex
Language: English
Status: Completed
Published: 2017-08-31
Updated: 2017-08-31
Packaged: 2018-12-22 05:30:10
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 2,403
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/11960703
Author URL: https://archiveofourown.org/users/Sinnychild/pseuds/Ked_from_safe-skeletons
Summary: Sans absolutely wants to try soul sex with Red. Red doesn't want to, but how can he not trust his lover in this matter?Beta-read byLazySintastic13!





	Karma is a bitch

**Author's Note:**

> I am really attached to this story because it's the first soul sex I wrote, and also the first story with a pretty heavy headcanon of my own in it. I really really hope you'll enjoy it <3 
> 
> You can find me on the tumblr [@sinful-skeletons](http://sinful-skeletons.tumblr.com) that I share with a fellow writer! Twice the stories, twice the fun!

“i wanna touch your soul so bad.”

“i'm sure it'd taste delicious. just like your magic. only  _ better _ .”

“that's not fair! i can't give you the same amount of pleasure you give me!”

“please, red, please,  _ please _ lemme touch your soul!”

* * *

Red remembered the first time Sans talked to him about that strange way to have sex. Without even touching your partner, one could give to them the most violent and intimate of pleasures, and share with them all of one’s thoughts and feelings. All you had to do was agree to manifest your soul and practically  _ abandon _ it.

The gold-toothed skeleton was horrified. Entrusting his soul, the very culmination of his being, to someone else? Letting it in the hands of a person who’d just have to clench their fist to dust him? That was against  _ everything _ he had ever been taught. Even if it were for Sans, he would never accept it; he was sure of it.

His lover had to deploy treasures of eloquence to convince him. Red, befuddled, had finally accepted to take the blue soul Sans had been practically throwing in his hands. The gold-toothed skeleton had instantly been fascinated. He had been overwhelmed by Sans’ emotions; for the first time in his life, Red had finally managed to believe he could be deeply, sincerely loved. Sans was at his mercy and offered him a sight of pure ecstasy, his soul was soft, warm and wet under Red’s touch. It had been a fantastic experience and he wasn’t afraid to do it again anymore. But still, he couldn’t swallow the idea of getting his own soul outside its shelter that was his rib cage.

And obviously, Sans never stopped to beg him to do so. The skeleton claimed that the situation was unfair, that their relationship felt unbalanced. He implored Red to let him brush his red soul, even by just a little, so that the latter would be able to go through the wonderful experience. He asserted that the fears were understandable but groundless, that Red could trust Sans just as the latter trusted him.

The skeleton had nothing in response to that.  _ Of course _ he trusted Sans... But giving away his soul to someone else was beyond a trusting act in his book. He had talked about it to his brother, lost and wanting to have some backup to oppose to his lover. Fell surely would understand, wouldn’t he?

* * *

“Let me get this straight. Sans wanna have soul sex with you. You already know what that does because you did it to him. And you  _ still _ refuse?”

“... are you fucking serious?”

“Well, I can understand.” The taller skeleton admitted. “I was quite embarrassed when Stretch told me about that at first. But stars, brother, if you had the slightest idea about how good it feels, you wouldn't mind it at all.”

* * *

Fell hadn’t be useful at all.

Though as flabbergasted as he was to learn that his brother didn’t have a problem with giving his soul to his lover, Red was forced to think about it. Fell was extremely wary. He had more troubles than him to get used to the softer universes of their loved ones. If he allowed himself to that practice, maybe Red could do the same…?

* * *

“please, red, please,  _ please _ lemme touch your soul!”

“o-okay.” Red stuttered.

Sans’ head shot up, eye sockets widened and his hand coming to a stand still. The skeleton was kneeled between his laid down lover’s legs, two fingers deep inside the ecto-cunt the latter had conjured for him. Red’s face, drowned in pleasure, made Sans want to give him more, _ much more _ , and he couldn’t help asking.

“sorry, what was that?”

“oh stars don't stop!”

“well, i need to be sure that was a real approval.” Sans insisted, slightly worried. “did you hear what i just said?”

Red’s cheekbones flushed red, as bright as the luminous heart under his ribs, and the skeleton looked away. Sans gently pulled his wet phalanges to let his lover pull himself together. He didn’t want to obtain a yes that would be regretted afterwards.

“y-yeah, i heard you. you know, i thought about it a lot recently… i know this isn’t fair and that i trust you enough to do this. i really don’t have any arguments to oppose you, so… maybe we could give it a try?”

Sans’ pupils shaped into hearts and Red felt himself blushing more under the absolute adoration his lover was giving him. Even though he loved the larger skeleton with all his soul, he had the feeling something wrong would happen, and he couldn’t manage to ignore that.

“for real?”

“b-but perhaps, we could use a safeword? if that’s okay?”

“anything you want! but i promise you won’t need it. and you know where i stand about making promises.”

“all right then. strawberry it is.”

“oh stars, you’ll never stop to remind me of that pie!”

“that wasn’t a pie, that was a disaster!”

Sans chuckled and, his pupils disappearing, dived onto his lover to kiss every inch of his skull. Soon enough, his tongue passed through his teeth and he began to stroke Red’s jaw and vertebrae. The latter arched his spine in response to the magic teasing all of the sensitive spots on his neck, barely aware that hands were wandering around his rib cage. That was intended. Carefully, now that Red was relaxed, Sans slipped his hands underneath the ribs and wrapped the small pulsating heart in his fingers.

A broken moan slipped through Red's teeth. He shut his eye sockets and his phalanges crinkled the sheets underneath.  _ That was… _ That was as if Sans’ hands were touching every each inch of his bones. Or rather, as if Sans’ magic was entirely wrapping him into this heavenly wetness. Maybe it was both of those things, and it was just so much more, all at the same time.

“stars i love you so much.” Sans whispered. “you're beautiful, sweetheart. you're so amazing when you look like this.”

What did Red looked like exactly? He didn’t have the slightest idea. Everything had disappeared around him the moment Sans took his soul away from his ribs, and felt fingers glide onto its surface. The larger skeleton, who had straightened up and shifted himself more comfortably on his lover, drank the sight offered to him.

Red was worn out on the mattress, eye sockets closed. The summoned magic in his pelvis seemed to be brighter and tinted the bones nearby with a beautiful red. His spine was arching, his tongue, lolled to the side of his jaw, matched the soft blush of his cheekbones. And the sounds he let slip through were truly delightful.

“oooh  _ f-fuck! _ sans this is so- _ oooh _ good!”

It only took a few minutes for the skeleton to become a moaning mess, and Sans himself found it hard to stay focused; waves of love sent by the gold-toothed skeleton’s soul overwhelmed him. Sans pushed in the most possible tender way a finger could into the throbbing heart, eager to see just how much he could pleasure his lover.

The whining became unrestrained cries intertwined with loving words. All of Red’s joints started to gleam, enlightening his whole body. Sans knew his lover by heart and saw the climax approaching. The larger skeleton was feeling over the moon and shut his eye sockets down, taking the soul dripping with magic near to his teeth. The blue tongue came out of his jaw again and...

* * *

“ _ holy shit! _ stop that fucking shit right now! fucking strawberry, please  _ please make it stop!” _

The howl of fear could never be confused with a cry of pleasure. Plus, the aching pain passing through Red hit Sans right in the face. Squeaking from the pain, Sans had made his tongue disappear even before hearing the safeword. He put back the red soul into the rib cage at a pace he could manage without hurting it, but Red couldn’t stop screaming.

Sans, terrified, finally noticed that the glowing heart was cowering under purplish magic. The second he saw it, the aggressive veil evaporated and the skeleton checked Red in an instant. Still 1 HP. He didn’t know how it could be possible, but the overwhelming relief swept the question away of his mind.

“oh my fucking stars, red, red i'm so  _ fucking sorry _ , are you okay? it's over, i put it away, i'm so so so sorry! please tell me you’re okay!”

The gold-toothed skeleton had sat up and hurriedly moved back to curl at the very end of the bed, far away as possible from Sans. His knees were up against his chin and his left eye flared with magic. Sans’ soul felt deeply hurt by the sight. Red was back to whom he was several months ago: wary, suspicious and jumping out as soon as you said something nice to him.

“ _ what the fuck did you do? _ ”

“i-i'm sorry, red, i didn't mean to! i didn't know it would do that! you had no problems with me!”

“and why the fuck should  _ you _ have a problem with me?”

“i don't fucking know, okay? The karmic retribution just started on its own when my magic touched your soul!”

“the karmic fucking what?”

“the karmic retri- what what?” Sans interrupted himself, befuddled by the asking.

“what is that  _ fucking shit _ you're talking about and why the  _ fuck _ did it attack my soul?!”

Sans watched carefully his lover. Red was all panicked, angry and was lacking understanding. It was obvious he wasn’t faking his ignorance. The larger skeleton felt stupid. Of course Red didn’t know what karmic retribution was! A judging ability was useless in a “kill or be killed” world. Sans felt sick to see his lover getting caught back by his past even in their bed. He wished he could have taken Red in his arms and erase all of his EXP by kissing him and murmuring gentle words to him.

“red, i'm so, so sorry... the karmic retribution is an ability judging the lv of enemies. The more lv you have, the more kr will hurt you. stars, i could have  _ dust _ you! i'm so fucking sorry! i don't even know how you didn't lose hp!”

Red didn’t move an inch, his arms wrapped around his legs, looking away from Sans’ gaze. He couldn't help himself but have this atrocious feeling to be a  _ prey _ all over again.

“maybe it didn't hurt my hp because we were not in a fight. but that  _ did _ hurt  _ me _ , trust me.”

“i know, i'm so mad at myself right now... it will never ever happen again. i won't bother you anymore with your soul, i won't even try to touch it under your rib cage! stars i was so scared!”

Sans’ hand reached out for Red’s, a begging look in his eye sockets.

“please, please forgive me. i didn't wanna hurt you. i'd do anything so you can forgive me. please, red, i love you.”

Red’s gaze went to the outstretched hand. The silence kept going. The gold-toothed skeleton was still shaking from the inconceivable pain that took over his body. Yet he knew Sans was telling the truth and would never intentionally hurt him - but it was beyond his control. One couldn’t erase years of paranoia with just a few months of happiness.

But this was Sans he was talking about here. And if Red couldn’t trust Sans anymore, then he’d be better off going back and turn to dust in his universe right now.

The skeleton sighed and reached a shy hand near to Sans’. He stayed curled up at the end of the bed though, incapable of moving more. His lover understood and got closer himself, slowly, like you would be around a wounded animal. Finally by his side, the larger skeleton wrapped the rattling bones in his arms.

* * *

And suddenly all of Red’s tension burst out while he gripped Sans, sobbing terribly. The former felt a hand land on his skull and it moved his head to rest against the latter’s rib cage; a blue heart glowing peacefully a few inches away of him. Both souls were standing still, slightly shaking from the fear. They eventually got to start pulsing, as they always did when the two skeletons were close enough, feeling the love of the other. It was slow, hesitant and quite offset, as if they had to get to know each other all over again.

But they finally synchronized and Red sighed in relief. Maybe this experience would only be a bad memory without consequences after all.

“… you lied to me.” Red noticed suddenly.

Sans looked down at him without understanding first, then his eye sockets widened.

“holy shit! see? this is why i never make promises! i should’ve shut the fuck up, i must have cursed us or something!”

Red choked on a chuckle and came a little bit closer to his lover.

“yeah, just like you made chara possess frisk because of your promise to toriel. you're the true evil of this world, ain't ya?”

“who could have guessed?”

Silence fell in between the skeletons as they simply cuddled, recovering from the atrocious pain and fear from earlier. Sans was drifting into sleep when Red’s voice made him slightly jump.

“hey, i just thought of something weird. isn’t stretch the one supposed to have that thing in underswap?”

“well, yeah, i guess. he’s the one fighting in the judgement hall. why?”

“because he doesn’t have it.”

“... what? how could you know that?”

Red wriggled in embarrassment. Did he really want Sans to know that he has looking for better excuses in asking his brother rather than trust his lover?

“promise you won’t be mad?”

“like hell i’ll promise. but yeah, i won’t be mad.”

“i figured that boss’d understand why i didn’t wanna have soul sex and, maybe, that he could come up with some backup. but this fucker only told me that i was stupid and that it was amazing. he did it with stretch, so surely stretch doesn’t have this karma stuff, does he?”

Sans stayed still for an instant.

“you’re probably right.” He admitted after some thinking.

He didn’t want to break the sweet atmosphere though, so he kissed Red on his forehead and the two skeletons fell asleep - Sans wondering how the fuck Stretch managed to gain LOVE.

**Author's Note:**

> So, this is a one-shot, but I will definitely use this idea with Stretch later. It just won't form a story, it'll be more like separated OS working canonically together ^^ I hope you liked it!


End file.
